Type-writing machine.



J. O. McLAUGHLIN.. TYPE WRITING MAGH'INE. APPLICATION FILED MAY 16, 1908.

907,632. I Patented Dec.22,1908.

UNITED sTAfrEs rAgENT onmon.

JOHN C. MCLAUGHLIN, OF JERSEY CITY, NEW. JERSEY, ASSIGNOR TO UNDERVJOOD TYPE- WRITER COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

TYPE-WRITIN G MACHIN E.

Application filed my 15; 190a. Serial No. 433,169.

Patented'Dec. 22, 1908.

' each line. It often happens, when a nervous operator To all whomit may concern: Be it known that 1, JOHN C. .MCLAUGHLIN a citizen of the United States, residing in: in the county of Hudson and, State of New Jerse haveinvented certain Jersey City,

new and useful mprovements ,Type- Writing Machines, of which the following is a specification.

'lhis invention relates to the pawl and ratchet mechanism for effecting the..: linefeeding movements of platens of typewriting machines. a

It is usual to employ a spring detent to en'- gage the ratchet wheel to position the l'at'n' accurately for successive lines, and, a 0 to hold the platen steady duringthe writing of gives an unusually quick stroke to the lever which operates the platen-driving awl, that the, platen overthrows. This is ue principally to the weight of the platen, the usual s ring detent being insufiiclent to arrest the Eaten at the proper oint when the platen as received unusual y great impetus from the jerky stroke of the spacing lever. The

platen is sometimes overthrown only a portion of a line-space, and durin the writing of 5 written letters to form a v {line instead of a straight line acrossthe page. 1

' received by tlre detent at the arrest of the opforcibly into the note a line it sometimeshappens that the spring detent, acting upon-the teeth of the ratchet wheel, gradually forces the platen back to its proper position; such radual back rotation of the platen having t e effect to cause the curved or slanting 'I he object 'ofthe present invention is to provide simple and inexpensive means for overcoming this disadvantage, particularly 'with a view to applying the dev'ice to exist- -machines. -n .tlie Underwood typewriting machine,

a spring- I provide upon this lever an extension or arm which I cause I tp arrest the platen-rotating lever and pawl;

ahdthe device is'so contrived that the shock erators hand serves to ress the detent more in the line-s ace ratchet wheel. Thus the greater the orce imparted to the line-space lever, .or the quicker the stroke of said lever, the greater is the power applied'to the line-space wheel space pawl-carrying s t age the to chebk the rotation of the platen, so that overthrow is avoided.

thereto; the parts shown in their positions at the arrest of the line-spacing pawl and the platen. Fig. 2 is a plan showing the line- 'de in engagement with eplaten-arresting or locking means. Fig. 3 is a 'view similar to Fig. 2, but showing the line space lever in normal position and out of engagement with the platen-arresting means. Fig. 4 is an end elevation of the line-spacing mechanism, showing the parts in operative or stroke-arresting positions.

Type-bars 1 strlke on the front of a platen 2, which is rotatably mounted by means of an axle 3 in platen frame ends 4, and carries a notched line-s ace Wheel 5. Upon a slide 6, mounted for ackward and forward sliding movement upon theplaten frame end 4, is pivoted a pawl 7, which isfo rced into engagement with the notches of the wheel 5 by a spring 7 whenever a backward movement is imparted to said slide by the usual lever 8, to rotate the platen. As usual, the

slide is returned forwardly to normal--position by a spring 9, and snnultaneouslythe means of a nose 10 on the pawl, said nose.

riding pawl 7 is wit awn from the; wheel 5 by upon a trip 11 formed upon a late 12,

which is ivoted at 12" to and is a justable backwar ly and forwardly by a finger-lever 13, for the "pur ose of regulating the'line spacing of the p aten. A detent lever. 14 is i'voted at 14 upon the platen frame end 4,

aving a roll 15 which by means of a spring 15* is normally pressed into one of the notches of the wheel 5 to hold the platen stea dy during writing. As so far described,

woo typewritiu machine,

I provide the etent 14 with a stop or arm 16 rojeeting 11 into the path of the slide 6, to he en aged by a projection 17 upon said slide at t e termination of a lineace stroke of the operating lever 8.. The s ock of arresting the lever stroke forces the arm 16 the arts are in common use on the Underbackward and crowds the detent roll 15 forwardforcibly-ififio thenotch the wheel 5, to lock the laten; so that th' quicker the strcke of t 1e lever 8,,the more powerful is the detent 14 to arrest thewheel and platen; whereby liability of overthrow of the platen is avoided.

latter to look the platen against overthrow.

2. In a typewriting machine, the combination with a revoluble platen, of a line space wheel connected to the platen, a spring detent for the wheel and ing a awl and operab the w eel and the platen, and means to enable said slide to cooperate with the detent to check or look the platen and prevent overthrow thereof.

In a typewriting machine, the combination with a revoluble laten, of a line-space wheel therefor normal y engaged by a spring detent, and a slide operable by a lever to rotate the platen; said dctent having a part projecting into the path. of the slide to be engaged thereby to force the detent against the wheel.

4. In a typewriting machine, the combination with a platen. and a notched line space wheel therefor, of a slide or carrier provided with a pawl normally out of engagement with the wheel, a lever to operate the slide and cause the pawl to rotate the platen, and a spring dctent pivoted upon the platen frame and comprising, both an arm having a roll normally en aging the line space wheel and an arm to be engaged by a projection on the slide at the termination of a line space stroke, to force the roll into the notch in'tho Wheel to check or locl: the platen against overthrow.

5. In a typowriting machine, the combination with a revoluble platen having a lines )ace wheel engaged by a spring 'cletent, and a slide havin a pawl and operable by a lever, of means to prevent overthrow of the platen, conmrising a st p projecting into the path of and engaged by the slide, said stop co-acting with the detent to force the detent against the line space wheel and lock the platen.

6.- In a typewriting machine, the combination with revoluble platen, a line space wheel therefor, and a lever-o erated slide having a pawl to engage the w eel to rotate the platen, of a sto -mounted on the platen frame in the path of said slide to be engaged thereby at the termination of the line-space platen, and a slide have by a lever to rotate stroke, and means for enabling saidstop to lock the platen against overthrow.

7. In a typewriting machine, the combination with a revoluble platen and a line-space wheel therefor, of a spring detent to engage the line-space wheel, a lever-operated slide carrying a pawl to turn said wheel and platen, and means to enable said slide to augment the force with which the detent engages the wheel at the termination of the platen-operating stroke of the lever.

8. In a typewriting machine, the combination with a revoluble platen and a line-space wheel therefor, of a spring detent to engage the line-space wheel, a lever and pawl to turn the wheel and platen and'a stop for the lever;

means being provided to enable the lever actlng through said stop to augment the power of the detent.

9. In a typewriting machine, the combina-- stop to lock the platen against overthrow.

10. In a typewriting machine, the combination with a revoluble platen, of a line-space wheel connected to the platen, a spring detent normally engaging the line-space wheel, a pawl to drive the line-space wheel, a lever to drive the pawl, and means to enable said lever to actuate said detent to check or look the platen against overthrow.

11. In a typewriting machine, thecombination with a revoluble platen, of a line-space wheel therefor, a spring detent normally engaging said line-space wheel, a lever having means to rotate the platen, and a part upon said detent projecting into the path of said rotating means to be engaged thereby to force the detent against the wheel.

12. In a typewriting machine, the combination with a platen and a notched line space wheel therefor, of platen-rotating means including a pawl normeily out of engagement with the wheel, a lever having means for driving the pawl to rotate the platen, and a spring detent pivoted upon the platen frame and comprising both an arm normally engaging the line-space wheel and an arm to be engaged by a member on said platen-rotating means at the termination of the line-space stroke, to force the spring detent against the line-space wheel to check or look the platen against overthrow.

JOHN C. MCLAUGHLIN,

Witnesses:

JOHN O. SEIFERT, K. FRANKFORT. 

